By Dylan R.N. Crabb
UPDATE (9/6/2017): The United States Supreme Court will hear oral arguments for Gill v. Whitford on October 3 of this year.
This week, the United States Supreme Court agreed to hear an appeal from the defendants in Gill v. Whitford, a federal court case from Wisconsin in which a panel of three federal judges struck down a redistricting plan from the Wisconsin legislature. US 7th Circuit Court Judge Kenneth Ripple and US District Court Judges Barbara Crabb and William Griesbach decided Wisconsin’s Act 43 to be unconstitutionally partisan last December in a federal lawsuit brought by twelve plaintiffs against five defendants.
The last time the Supreme Court heard arguments relating to voter redistricting was in 2004 with Vieth v. Jubelirer, the result of which which was a split vote among the court. The lingering issue from Vieth is an apparent lack of a measurable standard for excessive partisanship in drawing voter districts. However; the federal judges for the Western District of Wisconsin reference a new political measurement tool that may be able to calculate excessive partisanship: the efficiency gap.
According to the plaintiffs, in drafting Act 43, the Republicans employed two gerrymandering techniques: “cracking” — “dividing a party’s supporters among multiple districts so that they fall short of a majority in each one”— and “packing” — “concentrating one party’s backers in a few districts that they win by overwhelming margins,” in order to dilute the votes of Democrats statewide. This “cracking and packing result[ed] in ‘wasted’ votes: votes cast either for a losing candidate (in the case of cracking) or for a winning candidate but in excess of what he or she needs to prevail (in the case of packing).” They therefore urge the court to adopt a new measure for assessing the discriminatory effect of political gerrymanders — the efficiency gap (or “EG”). “The efficiency gap is the difference between the parties’ respective wasted votes in an election, divided by the total number of votes cast.” When two parties waste votes at an identical rate, a plan’s EG is equal to zero. An EG in favor of one party, however, means that the party wasted votes at a lower rate than the opposing party. It is in this sense that the EG arguably is a measure of efficiency: Because the party with a favorable EG wasted fewer votes than its opponent, it was able to translate, with greater ease, its share of the total votes cast in the election into legislative seats. In short, the complaint alleges that Act 43 purposely distributed the predicted Republican vote share with greater efficiency so that it translated into a greater number of seats, while
purposely distributing the Democratic vote share with less efficiency so that it would translate into fewer seats (180 F.Supp.3d 583, US District Court, Wisconsin, 2016).
The efficiency gap is a mathematical tool to calculate the total number of votes cast in an election along with the number of “wasted votes” (the votes one candidate receives in excess of the number needed to win) for a specific candidate. The number of wasted votes divided from the total number of votes provides the efficiency gap. This mathematical measurement was developed in part by Nicholas Stephanopoulos, an assistant professor of law at the University of Chicago. The presumption in the efficiency gap method is simple: the greater the efficiency gap in favor of a particular candidate, the more likely that candidate’s party may have gerrymandered the voting district.
The efficiency gap may be the answer the Supreme Court has been looking for in its search for a measurable standard in determining partisanship and, if the Court affirms the decision of the Judges Ripple, Crabb, and Griesbach in Wisconsin, it will allow other district courts to decide for or against redistricting in their state. Those potential cases can have an impact on redistricting after the upcoming 2020 census.
The specific questions before the Supreme Court regarding Gill v. Whitford are as follows:
- Did the federal court for the Western District of Wisconsin violate Vieth v. Jubelirer, 541 US 267 (2004), when it held that it had the authority to entertain a statewide challenge to Wisconsin’s redistricting plan, instead of requiring a district-by-district analysis?
- Did the district court violate Vieth when it held that Wisconsin’s redistricting plan was an impermissible partisan-gerrymander, even though it was undisputed that the plan complies with traditional redistricting principles?
- Did the district court violate Vieth by adopting a watered-down version of the partisan-gerrymandering test employed by the plurality in Davis v. Bandemer, 478 US 109 (1986)?
- Are defendants entitled, at a minimum, to present additional evidence showing that they would have prevailed under the district court’s test, which the court announced only after the record had closed?
The broader question for the American public revolves around state legislatures having the power to redraw their voting districts after each census. Currently, the American states of Arizona, California, Hawaii, Idaho, Montana, New Jersey, Washington, Alaska, Arkansas, Colorado, Missouri, Ohio, Pennsylvania, and Iowa have taken redistricting power from their respective legislatures and placed it under the jurisdiction of an independent commission. Should the state of New Mexico follow-suit with that electoral strategy?